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Solid polymer electrolytes provide an alternative approach to providing improved safety whilst concurrently acting as a performance enhanced separator within Lithium-ion batteries (LIBs). This investigation studies the effects of Lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) salts in a polymer blend with Polyvinylidene fluoride (PVDF) and Poly (vinylpyrrolidone) (PvP) or Poly (4-vinylpyridine) (P4VP) on the performance of SPE membranes. Characterization by X-ray diffraction and Fourier-transform infrared spectroscopy highlights the changes due to LiTFSI, specifically amorphization. Performance studies with increasing LiTFSI showed improved thermal stability and the inhibition of PVDF endotherms on differential scanning calorimetry (DSC) profiles. The drawbacks of increased LiTFSI content were evident on the mechanical performance with decreased thresholds on the tensile strength. Inversely, improvements on the dielectric performance and conductivity were observed with excellent workability from a wide electrochemical stability window of 0.5 to 3.64 V vs. Li+/Li. Additionally, the incorporation of metal-fillers; Aluminum Oxide, Zirconia Oxide and Silicon Oxide was similarly studied.

Hybrid composites between Germanium (Ge) and carbonaceous materials are promising anode materials for Li-ion batteries (LIBs). The mitigation of reduced cycling ability and rate capability allows for the unhindered benefit of higher capacities in Ge-based anodes. Here, the effect of Ge mass loading on the electrochemical performance of GeO2/Ge/r-GO composites was evaluated as LIBs anode. GeO2/Ge/r-GO composites were synthesized by controlled microwave radiation of ball-milled Ge and sonicated dispersion of graphene oxide (GO). The composite anode at Ge 25% showed greatest cycling retention with 91% after 100 cycles and an average specific capacity of 300 mAh/g (1600 mAh/g Ge). At 75% Ge mass loading the anode suffered with limited cycling retention of 57.5% at the cost of greater specific capacities. The composite at 50% Ge attained advantageous characteristics of both composites with a stable cycling performance of 71.4% after 50 cycles and an average specific capacity of 400 mAh/g (1067 mAh/g Ge). These findings can be used to shape high-energy Ge-based anodes and guide future development in energy storage.